Method for operating a water-containing appliance and water-containing appliance

ABSTRACT

The invention relates to a method and device for carrying out said method in order to fully dissolve impurities in the cleaning fluid and thereby avoid turbidity in said cleaning fluid. According to the invention, the degree of impurity in said cleaning fluid is determined in at least one partial program step by means of wet combustion and the degree of combustion is established and the above-mentioned method is carried out in a water-guiding device.

The invention relates to a method for operating a water-containingappliance and a water-containing appliance for operating this method.

Water-containing appliances presently on the market, e.g. dishwashers,especially domestic dishwashers or washing machines, especially domesticwashing machines, usually have a control device—a programcontroller—with which a cleaning program, which can be composed ofpartial program steps, is operated and on which a cleaning programselected by the user with pre-set and/or selectable parameters can beset.

In contrast however, a method for operating a dishwasher—awater-containing appliance—has become known from DE 1 96 51 344 A1 inwhich at the beginning of the program the dishwasher is merely set inoperation and the parameters to be set for the continuation of thecleaning process are set depending on at least one detected parameternecessary for the continuation of the cleaning process and influenced byit, wherein at least one parameter is determined by means of a turbiditysensor from the turbidity of the cleaning liquid and whereby acompletely automatically controlled method for operating a dishwasher—awater-containing appliance—is created in which incorrect operation bythe user is completely eliminated and whereby the power and waterconsumption of the basically automatic dishwasher is restricted to thelowest possible level.

A disadvantage with using a turbidity sensor according to the methoddescribed previously however is that contaminants of the cleaning liquidwhich are completely dissolved in the cleaning liquid, and in thissituation produce no turbidity of the cleaning liquid, naturally cannotbe identified. In such a case, therefore, it is not possible todetermine the cleaning state of the items to be cleaned using turbiditysensors.

In practice, it has been found that organic substances in particularhave this property. Since the items to be cleaned in water-containingappliances, e.g. dishwashers or washing machines, are mainlycontaminated with organic residue—food remains, sweat, skin particlesetc, detection using a turbidity sensor is not suitable for determiningthe degree of cleaning of the items to be cleaned in relation to thecleaning from soluble organic contaminants.

It is thus the object of the invention to provide a method and a devicefor operating this method with which contaminants of the cleaning liquidwhich dissolve completely in the cleaning liquid and in this caseproduce no turbidity of the cleaning liquid, can be identified.

This object is solved by the method according to the invention with thefeatures according to claim 1 and the water-containing appliance withthe features according to the further independent claim. Advantageousfurther developments of the inventions are characterised in thedependent claims.

According to the method for operating a water-containing applianceaccording to the invention, in at least one partial program step thedegree of contamination of the cleaning liquid is determined by means ofa wet combustion and determining the combustion quantity.

In a so-called wet combustion organic components contained in liquidsare oxidised (“burnt”). From the combustion quantity, for example, inthe case of the cleaning liquid in a dishwasher or washing machine it ispossible to determine how much invisible dissolved organic residue iscontained in the liquid and thus to determine the degree of cleaning ofthe items to be cleaned. The invention has succeeded in providing amethod with which contaminants of the cleaning liquid which dissolvecompletely in the cleaning liquid and in this case produce no turbidityof the cleaning liquid can be identified.

According to a preferred feature of the invention, a pre-determinedquantity of ozone is passed into, passed through and passed out of apartial quantity of the cleaning liquid and the quantity of ozone whichis passed out is measured by means of at least one arranged sensor andcompared with the quantity of ozone which was passed in. It is knownthat ozone (O₃) is completely constructed of oxygen atoms and is ahigh-energy form of oxygen and that ozone reacts rapidly especially withhydrocarbons, the hydrocarbons being converted into CO₂ and eliminated.This explains the use of ozone in sterilising, disinfecting and cleaningagents (see, for example, EP 0 716 686 B1). Ozone is barely soluble inwater which is why any falsification of the measurement result bydissolution of the ozone in the liquid to be measured is not to beexpected.

The disinfection and deodorising of an interior of a microwave oven(DE-OS 39 04 418) and the deodorising of a dishwasher using ozone (seeDE-OS 39 21 177) are also known. The treatment of supplied washingliquid by ozone for disinfection and deodorising (see DE-OS 35 40 335)is also known.

The method according to the invention is executed with said advantagesusing the water-containing appliance according to the invention.

The quantity of ozone which is passed out is preferably measured usingat least one arranged sensor and compared in a control device with thequantity of ozone which is passed in.

In an especially advantageous fashion the program sequence of thewater-containing appliance can be changed on the basis of the result ofthe comparison. Should it now be found that the quantities areapproximately the same, the items to be cleaned are completely freedfrom organic substances and termination of the cleaning process can beinitiated. However, should it be found that the quantities aredifferent, the cleaning process is continued in any case.

Advantageously, on the basis of the result of the comparison,corresponding parameters of the program sequence of the water-containingappliance can be changed according to the difference determined betweenthe quantities. Thus, according to the difference determined between thequantities, i.e., according to the degree of cleaning of the items to becleaned which has already been achieved, measures can be introduced viathe control device of the water-containing appliance, which for examplebring about more intensive cleaning, i.e., higher temperature or longerrunning time etc.

In the water-containing appliance according to the invention it isfurthermore advantageous that the residual quantity of ozone which ispassed out again, acts directly on the items to be cleaned and there canassist the cleaning action of the cleaning agent used and/or contributeto the deodorising. The cleaning action of the cleaner is betteractivated by the action of the ozone whereby the use of tensides usuallycontained in such cleaning agents can be reduced. Ozone also has ableaching effect especially on contaminants adhering to the items to becleaned which can be utilised by acting on the items to be cleaned. Thebleaching effect on the contaminants reduces the adhesion of thecontaminants on the items to be cleaned and thus brings about faster andbetter cleaning. The ozone naturally also acts advantageously throughthe wet combustion in cleaning the remaining cleaning liquid.

According to an advantageous embodiment of the water-containingappliance according to the invention, after the end of the cleaningprocess ozone is fed into the interior of the appliance whereby adisinfection of the appliance interior and if desired and if these arestill present, also of the items to be cleaned is achieved.

1-8. (canceled)
 9. A method for operating a water-containing appliance,comprising: subjecting a partial quantity of cleaning liquid in theappliance to a wet combustion treatment that combusts organic matterthat may be present in the partial quantity of the cleaning liquid; andcharacterizing the presence of organic matter in the cleaning liquidbased upon the wet combustion results.
 10. The method according to claim9, wherein a pre-determined quantity of ozone is passed in, passedthrough and passed out of a partial quantity of the cleaning liquid andthe quantity of ozone which is passed out is measured and compared withthe quantity of ozone which is passed in.
 11. A water-containingappliance, comprising: means for providing a partial quantity of avolume of a cleaning liquid in the appliance; and means for subjectingthe partial quantity of cleaning liquid in the appliance to a wetcombustion treatment that combusts organic matter that may be present inthe partial quantity of the cleaning liquid and for characterizing thepresence of organic matter in the cleaning liquid based upon the wetcombustion results.
 12. The water-containing appliance according toclaim 11, wherein the quantity of ozone which is passed out is measuredby means of at least one arranged sensor and is compared in a controldevice with the quantity of ozone which is passed in.
 13. Thewater-containing appliance according to claim 11, wherein on the basisof the comparison, the program sequence of the water-containingappliance can be changed.
 14. The water-containing appliance accordingto claim 11, wherein on the bases of the result of the comparison,corresponding parameters of the program sequence of the water-containingappliance can be changed in accordance with the difference determined inthe quantities.
 15. The water-containing appliance according to claim11, wherein the ozone which is passed out is passed onto the items to becleaned.
 16. The water-containing appliance according to claim 11,wherein after the end of the cleaning process ozone is fed into theinterior of the appliance.